• Title/Summary/Keyword: Cu,Zn-superoxide dismutase

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Oxygen Toxicity of Superoxide Dismutase-Deficient Saccharomyces cerevisiae by Paraquat (Paraquat에 의해 유도된 Superoxide Dismutase 결핍 효모의 산소 독성)

  • 김지면;남두현용철순허근
    • KSBB Journal
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    • v.10 no.5
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    • pp.561-567
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    • 1995
  • Using superoxide dismutase (SOD)-deficient mutants of Saccharomyces cerevisiae, the oxygen toxicity induced by paraquat was studied. In aerobic culture condition, yeasts lacking MnSOD (milochondrial SOD) showed more significant growth retardation than CuZnSOD (cytoplasmic SOD)-deficient yeasts. However, not so big differences in growth pattern of those mutants compared with wild type were observed under anaerobic condition. When exposed to paraquat, the growth of yeasts lacking CuZnSOD was severely affected by higher than 0.01mM of paraquat in culture medium. By the analysis of several cellular components ivolved in free radical generating and scavenging system, it was found that, under aerobic condition, the content of lipid peroxides in cell membrane as well as cellular activity of glutathion peroxidase of CuZnSOD-deficient mutants was increased in the presence of paraquat, although significant decrease of catalase activity was observed in those stratns. In MnSOD-deficient yeast, however, increment in cellular activity of glutathion peroxldase and catalase by paraquat was observed without any deterioration of membrane lipid. It implies that the lack of mitochondrial SOD could be compensated by both of glutathion peroxldase and catalase, but that only glutathion peroxidase might act for CuZnSOD in cytoplasm. In contrast, all of SOD-deficient mutants showed a significant decrease in catalase activity, but slight increase in the activities of glutathion peroxidase, when cultivated anaerobically in the medium containing paraquat. Nevertheless, any significant changes of lipid peroxides in cell membranes were not observed during anaerobic cultivation of SOD-deficient mutants. It suggests that a little amount of free radicals generated by paraquat under anaerobic condition could be sufficiently overcome by glutathion peroxidase but not by catalase.

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Protective Effects of Antoxidant Enzymes of Candida albicans against Oxidative Killing by Macrophages

  • Kim, Hye-Jin;Na, Byoung-Kuk;Kim, Moon-Bo;Park, Duk-Young;Song, Chul-Yong
    • Journal of Microbiology
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    • v.37 no.2
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    • pp.117-122
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    • 1999
  • Protective roles of antioxidant enzymes, copper-zinc superoxide dismutase (CuZnSOD), manganese superoxide dismutase (MnSOD), and catalase of Candida albicans against exogenous reactive oxygens and oxidative killing by macrophages were investigated. The initial growth of C. albicans was inhibited by reactive, oxygen-producing chemicals such as hydrogen peroxide, pyrogallol, and paraquat, but it was restored as the production of antioxidant enzymes were increased. The growth inhibition of C. albicans by reactive, oxygen-producing chemicals was reduced by treating the purified candidal SOD and catalase. Also, in the presence of SOD and catalase, the oxidative killing of C. albicans by macrophages was significantly inhibited. These results suggest that antioxidant enzymes, CuZnSOD, MnSOD, and catalase of C. albicans may play important roles in the protection of C. albicans not only from exogenous oxidative stress but also from oxidative killing by macrophages.

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Cloning and Characterization of the Cu,Zn Superoxide Dismutase (SOD1) cDNA from the Spider, Araneus ventricosus

  • Choi Young Soo;Choo Young Moo;Li Jianhong;Sohn Hung Dae;Jin Byung Rae
    • International Journal of Industrial Entomology and Biomaterials
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    • v.10 no.1
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    • pp.73-77
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    • 2005
  • A Cu,Zn superoxide dismutase (SOD1) cDNA was cloned from the spider, Araneus ventricosus. The A. ventricosus SOD1 (AvSOD1) cDNA contains an open reading frame of 495 bp encoding 165 amino acid polypeptide with a predicted molecular mass of 17,114 Da and pI of 6.55, and possesses the typical metal binding ligands of six histidines and one aspartic acid common to SOD1s. The deduced amino acid sequence of the AvSOD1 cDNA showed $51\%$ identity to Ceratitis capitata SOD1, and $50\%$ to SOD1 sequences of both Drosophila melanogaster and Chymomyza amoena. Northern blot analysis revealed the presence of AvSOD1 transcripts in all tissues examined.

Improvement of Drought Tolerance in Transgenic Tobacco Plant (형질전환 담배의 내건성 개선)

  • Park, Yong Mok
    • Journal of Environmental Science International
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    • v.25 no.1
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    • pp.173-179
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    • 2016
  • Leaf water and osmotic potential, chlorophyll content, photosynthetic rate, and electrolyte leakage were measured to evaluate tolerance to water stress in wild-type (WT) and transgenic tobacco plants (TR) expressing copper/zink superoxide dismutase (CuZnSOD) and ascorbate peroxidase (APX) in chloroplasts. Leaf water potential of both WT and TR plants decreased similarly under water stress condition. However, leaf osmotic potential of TR plants more negatively decreased in the process of dehydration, compared with WT plants, suggesting osmotic adjustment. Stomatal conductance (Gs) in WT plants markedly decreased from the Day 4 after withholding water, while that in TR plants retained relatively high values. Relatively low chlorophyll content and photosynthetic rate under water stress were shown in WT plants since $4^{th}$ day after treatment. In particular, damage indicated by electrolyte leakage during water stress was higher in WT plants than in TR plants. On the other hand, SOD and APX activity was remarkably higher in TR plants. These results indicate that transgenic tobacco plants expressing copper/zink superoxide dismutase (CuZnSOD) and ascorbate peroxidase (APX) in chloroplasts improve tolerance to water stress.

Anti-aging Activity of Aralia Cordata Thunb. by Inhibiting Oxidized Low-dencity Lipoprotein Production in Rats

  • Hyun, Min-Kyung;Jeong, Ji-Cheon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.21 no.6
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    • pp.1576-1580
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    • 2007
  • Aralia cordata Thunb. (Araliaceae, ACT) is an remarkable herbal plant that has been widely used in traditional oriental medicine for the treatment of inflammatory diseases and cardiovascular disorders. In this study, we have established a vascular aging model in rats by orally administrating excessive vitamin $D_2$ (500,000 IU/kg/day) for 4 days followed by feeding high cholesterol diet for 16 weeks and then rats were randomly divided into control group, high cholesterol diet (HCD) group, HCD+ACT (30 mg/kg) and HCD+ACT (60 mg/kg) group. ACT (30, 60) significantly reduced total cholesterol (TC) content compared with HCD, but no significant differences in the serum lipids. Secondly, we measured the serum levels of Oxidized Low-dencity Lipoprotein (OxLDL) and malondialdehyde (MDA) in order to further investigate the anti-vascular aging mechanism of ACT. The results, ACT (30, 60) treatments decreased OxLDL, MDA content and increased Cu/Zn superoxide dismutase activity compared with HCD treatments. The results suggested that ACT inhibited OxLDL production rather than serum lipids lowering and that ACT could be used as potential anti-atherosclerotic agent in aged cells.